Connecting Geometry - Cathleen V. Sanders
A fully credited high school distance learning geometry course offered via the Internet to students throughout the Hawaiian islands as part of a grant-funded pilot project through the Hawaii Department of Education. During this E-School (electronic school)
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Continental Mathematics League (CML)
Information about the Continental Math League, including samples and solutions from CMLs for grades two and three, Pythagorean for grades 4-9, Euclidean for grades 4-9, and calculus. Also, order Best of CML books containing questions, and obtain the competition's
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CopyCat - Jim Morey
A Java game that revolves around replicating a picture created by several patterned faces of a solid object (like a cube), challenging the mind to understand complex geometrical structures and symmetry. To do well at the game, the player must first become
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Count Down to Fall - Fran Hawk, Sherry Neidigh (ill.)
Seasonal counting fun with this picture book. This title also includes the Sylvan Dell “For Creative Minds” section with lessons like “Plant Parts,” “The Shape of It All,” and “Match the Leaves.” Check out all these activities at the book homepage, along
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The Counterfeit Coin - Ivars Peterson (MathTrek)
The classic puzzle of the counterfeit coin has long served as a stiff test of one's reasoning power and ingenuity. In its standard form, the problem concerns 12 coins identical in size, shape, and appearance. One coin, however, is counterfeit, having
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The Counting Game - Chris Malumphy
A game for children starting to count, showing a number of objects and asking you to click on the correct number button. A thermometer graphic tells you when you have correctly answered ten questions.
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Count Madness Number Puzzles - James E. Garner
Cards with questions covering a wide range of subjects, each of which can be answered with a counting number. Answers are upside-down on the card. Examples and ordering information provided on site. Teacher's copy available.
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Count On - Department for Education and Employment, UK
Activities and resources -- some simple and some fancy -- for parents, teachers, and students. Resources offers, among other things, guides: to mathematical misconceptions; for parents helping with homework; for promoters of math fairs; and for providers
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The Cow in the Classroom - Ivars Peterson (MathLand)
Math Curse by Jon Scieszka and Lane Smith spoofs the types of word problems that educators and textbook writers invent to dress up arithmetic exercises and, supposedly, to demonstrate the relevance of math to everyday life. Canadian economist and humorist
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Cracking a Medieval Code - Ivars Peterson (MathTrek)
The first printed book on cryptology was written by Johannes Trithemius (1462-1516), an abbot in Spanheim, Germany, who was one of the leading intellectuals of his day. Bearing the title Polygraphiae libri sex ("Six Books of Polygraphy"), it was published
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Creative Java Puzzles - J. L. Read, Enchanted Mind
Games "good for exercising both sides of the brain." Knight's Tour: pass all the squares of the board with the knight, making only legal moves. Peg Solitaire: Remove all the pegs in the least amount of time, finishing with only one peg in the target hole.
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Crossnumber puzzle (figure logic) - Alfredo Baratta
Cross figure puzzles to print or play online. Also known as figure logic puzzles, cross figure puzzles resemble crosswords in structure, but with entries consisting of numbers rather than words, and clues based on math questions, e.g., "1 Across: The
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Cross Number Puzzles - Rainer Typke
Cross number puzzles to solve online; log in to create your own. Also known as crossfigure, figure logic, or numberlock puzzles, cross number puzzles require numbers instead of words to complete a crossword-like grid.
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Cryptarithms Online - Jorge Soares
Mathematical puzzles in which the digits are replaced by letters of the alphabet or other symbols. Brain-teasers by the author; cryptarithms from the journal Sphinx; a primer; books on cryptarithms, and links to relevant sites on the Web.
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Cryptoclub - Vera Pless, Janet Beissinger
This website includes tools to encrypt and decrypt messages, an
animated treasure hunt, a classroom message board to send and
receive encrypted messages, and a place to explore mathematics
topics related to cryptography, such as prime numbers and
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Cryptography - Corey Reed
An introduction to cryptography, in particular affine enciphering applied to the alphabet, focusing on the use of linear algebra. Includes a primer on bases and modulus algebra and extensions for deciphering an affine enciphered message, using keys to
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CTAP Middle School Math Project - CTAP Region IV
A database of online technology resources supporting California middle school math content standards for grades 6, 7, and algebra. Designed for use in classroom instruction or as homework helpers for students, the matrices resources align to state standards
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C.T.J. Dodson - Christopher Dodson
Dodson provides notes and Maple or Mathematica packages for many different mathematics courses, including algebra and pre-calculus, calculus, differential equations, using computers for mathematics and statistics, and an introductory course on curves,
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The Curious Creative: Maths - Tom Barrett
Blog by a former teacher and ICT Subject Leader. Barrett's math posts, which date to back to July, 2006, have included "Addressing the Balance: Multiflyer Times Tables Challenge," "Using Nintendo Wii Sports for Addition and Subtraction," "My Maths Lesson
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The Cutting Sticks Problem - Frans Faase
A classic math puzzle: You are given k sticks with integer length of which the total length of sums up to n(n+1)/2. None of the sticks is shorter than n. Can you always cut them into sticks with length 1, 2, up to n, no matter the number of the sticks
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CyMath
Step-by-step typeset results in differential calculus, integral calculus, algebra, and trigonometry. Just key in your expression or equation — or modify one of CyMath's examples — then select from among eight actions in the pull-down menu:
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Data Games - KCP Technologies
As students play Data Games, they generate data that they must analyze to win the games. Supporting materials include a student worksheet; teacher guidelines that correlate the activity to the Common Core State Standards for Mathematics (CCSSM); and videos
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